"Moreover we are even found to be false witnesses of God, because we testified against God that He raised Christ , whom He did not raise, if in fact the dead are not raised" (NASB)
Something I'm pretty sure of is that I don't want to be a false witness against God. So, if I say "The New Testament is inspired, inerrant, Holy Writ" and it's not true, I've sinned.
Something else that bothers me are the endings of 2 and 3 John. 2 John 1:12 and 3 John 1:14 both mention that John had much to tell the recipients of the letter, but that he would rather tell them "face to face". If I knew I was writing Scripture, I'd want to be as lengthy as possible, not missing any details. If I were aware that my writings were going to be read for thousands of years, I don't think I'd write a short letter that pretty much repeats exactly what I've already written (1 John). It seems that what he had to tell them was far more important than writing it out on some papyri (or a scroll, depending upon who you read). In other words perhaps the Gospel is more important than any of the gospels.
Two arguments I hear for the inspiration/inerrancy (not the same things, but these arguments are used for both...and naturally if they aren't inspired, they aren't inerrant):
1)Scripturally:I hear 2 Timothy 3:16 thrown around as if we can assume that Paul had the NT mind. He may have it in mind, but I need more proof than just citing the verse. 2 Timothy would've been written when some of the books of the NT had not yet been written. How do we explain that? Another argument from Scripture is the use of 2 Peter 3:16. This is a bit more convincing that at least some of Paul's letters are Scripture, in Peter's view. However, which ones? Are we sure we have all the letters? I'm not conspiring here, I just mean that Paul's epistles are occasional and sometimes personal, so can we be sure that we have them all?
2)Historically: A great many contemporary scholars will disagree with me here, but...I believe that there were atleast some churches (perhaps Jerusalem, Alexandria, and Oxyrhynchus) that had complete copies of the NT as we have it by the end of the first century/very early in the 2nd century. Most people who appeal for the canonicity will appeal to the historical understanding of the canon from the early church. But, just because historically someone did something doesn't make it right. In other words, like N.T. Wright mentions in The New Testament and the People of God, we shouldn't immediately assume that the early church is normative for all of Christianity. An appeal to the earliest understanding may not be the right way to go. Perhaps they were mistaken. Perhaps they needed their book to be Scripture too (compared to the OT).
So, if you've made it all the way through this post, you may think me a heretic. Quite alright. Whether you think I'm a heretic or not, I want you to suggest some reading. The overall question is: Why should I think the New Testament is Scripture?